Sometimes getting communication from a customer who only kind of wants to contact you is well worth the effort.

Why would you want to talk only to customers who "really want" to talk to you? Instead of all your customers, who are a superset of that group and don't always have the same needs?

What about all the emails that get sent to people who aren't customers yet and just have a simple question that isn't covered by the FAQ?

They'll see noreply@, and not bother to dig up a support email address and forget about your company's offerings.

However, seeing a welcoming replieswelcome@ email, they can ask their simple question while they're thinking of it, which then becomes a warm lead, and possibly even convert into a paying customer.

I did get the Ian Malcolm reference.